1. Raine et al (1997) Brain abnormalities in murderers
Brain abnormalities in murderers indicated by positron emission tomography
Biological Psychiatry
Mark Souter psychlotron.org.uk

2. Raine et al (1997) Brain abnormalities in murderers
Introduction
is there a biological basis for criminality?
PET scans
radioactive labels on:
blood/blood sugars
dopamine (neuro-transmitter)
 gamma ray signals
7-8M ps
also MRI and fMRI
Mark Souter psychlotron.org.uk

3. Raine et al (1997) Brain abnormalities in murderers
Mark Souter psychlotron.org.uk
PET scans showing ‘hot spots’ for cognitive activities

4. Raine et al (1997) Brain abnormalities in murderers
introduction: problems
colourisation v complex  errors
'hot spots' same for 'on & 'off' brain actions
practiced brain activity declines in that area
'hottest spots' = only for newest tasks?
"it seems we should not let the quality of evidence get in the way of a good story" Banyard and Grayson 2000
Mark Souter psychlotron.org.uk

5. Raine et al (1997) Brain abnormalities in murderers
PET scan of a subject whilst practicing a new language skill
A scan of the same subject demonstrating this skill after it had become familiar
Mark Souter psychlotron.org.uk

6. Raine et al (1997) Brain abnormalities in murderers
the study: subjects
41 people: 39M 2F
charged with murder
pleading not guilty by reason of insanity (NGRI)
all referred for PET for legal reasons
average age 34.3
Mark Souter psychlotron.org.uk

7. Raine et al (1997) Brain abnormalities in murderers
the study: subjects’ medical histories
schizophrenia 6
head injury/organic brain damage 23
drug abuse 3
affective disorder 2
epilepsy 2
hyperactivity or learning disorder 3
personality disorder 2
Mark Souter psychlotron.org.uk

8. Raine et al (1997) Brain abnormalities in murderers
the study: controls
1 for each subject
matched for age / sex
schizophrenics with non-murderer schizophrenics
all controls screened for mental/physical health
Mark Souter psychlotron.org.uk

9. Raine et al (1997) Brain abnormalities in murderers
the study: the PET process
injection with glucose tracer
32 mins on target recognition task
NRGI/controls compared re 14 L&R brain areas
6 cortical:
inc prefrontal; parietal; temporal; occipital
8 sub cortical:
inc corpus callosum; amygdala; hippocampus
Mark Souter psychlotron.org.uk

10. Mark Souter psychlotron.org.uk

11. Raine et al (1997) Brain abnormalities in murderers
the study: ANOVA
statistical comparison
ANalysis Of VAriance
compares a range of factors
Mark Souter psychlotron.org.uk

12. Raine et al (1997) Brain abnormalities in murderers
results: cortical areas
differences in activity in lobes of cerebral cortex cf controls;
parietal & pre-fontal: less activity =?
occipital: more activity =?
temporal: same =?
Mark Souter psychlotron.org.uk

13. Raine et al (1997) Brain abnormalities in murderers
results: sub cortical areas
less activity in corpus callosum cf controls
a sub-cortical area =?
cf Sperry
Mark Souter psychlotron.org.uk

14. Raine et al (1997) Brain abnormalities in murderers
results: sub cortical areas
imbalance between hemispheres cf controls in;
amygdala; hippocampus – less activity L / more R
thalamus - more activity R / same L
handedness made no difference
ethnicity made no difference
head injury patients’ corpus callosum only difference
Mark Souter psychlotron.org.uk

15. Raine et al (1997) Brain abnormalities in murderers
discussion: authors (1)
supports previous findings;
amygdala (part of limbic system) differences (linked to emotions; lack of fear)
corpus callosum differences linked to lack of long term perspective?
cautious about implications
Mark Souter psychlotron.org.uk

16. Raine et al (1997) Brain abnormalities in murderers
discussion: authors (2)
results;
do not show violence is only biological in origin
do not show NGRIs not responsible for their own actions
do no say anything about causes of differences
cannot be generalised from NGRIs to other violent offenders
cannot be generalised to other types of crime
Mark Souter psychlotron.org.uk

17. Raine et al (1997) Brain abnormalities in murderers
discussion: other issues
imaging methods still being developed
pre-scan task no bearing on violent behaviour
NGRIs not necessarily charged with violent act
cause  effect of brain differences unclear
Mark Souter psychlotron.org.uk

18. Raine et al (1997) Brain abnormalities in murderers
discussion: practical applications
diagnosis of criminality?
no clear evidence to support this
treatment of criminality
Mark Souter psychlotron.org.uk

19. Raine et al (1997) Brain abnormalities in murderers
discussion: summary
data unclear
differences small
cause-effect unknown
meaning of differences unknown
Mark Souter psychlotron.org.uk